A 3D Printed H-Plane Horn Antenna with Size Reduction by Permittivity Control

A 3D printed H-plane horn antenna aiming for a size reduction and low fabrication cost is presented in this work. The proposed H-plane horn filled with dielectrics of different relative electric permittivity provides phase compensation at the antenna aperture and a compact structure. The electromagnetic field propagating inside the horn is controlled by varying the relative permittivity of a composite resin - Al2O3and air, forcing the cylindrical wave to transform into a plane wave. Our proposed approach offers a reduction in the horn’s length by about 36% c.f. the air-filled horn of the same gain, without considering the dielectric loss. Simulation results show that at 20 GHz, for the length of the horn of one free-space wavelength, the antenna provides a gain of 6.3 dBi, 38° half-power beamwidth in H-plane, and 26 dB front-to-back ratio.